J/ApJ/752/95 PHAT stellar cluster survey. I. Year 1 (Johnson+, 2012)
PHAT stellar cluster survey.
I. Year 1 catalog and integrated photometry.
Johnson L.C., Seth A.C., Dalcanton J.J., Caldwell N., Fouesneau M.,
Gouliermis D.A., Hodge P.W., Larsen S.S., Olsen K.A.G., San Roman I.,
Sarajedini A., Weisz D.R., Williams B.F., Beerman L.C., Bianchi L.,
Dolphin A.E., Girardi L., Guhathakurta P., Kalirai J., Lang D.,
Monachesi A., Nanda S., Rix H.-W., Skillman E.D.
<Astrophys. J., 752, 95 (2012)>
=2012ApJ...752...95J 2012ApJ...752...95J
ADC_Keywords: Photometry, HST ; Clusters, globular ; Surveys ; Galaxies, optical
Keywords: catalogs; galaxies: individual: M31; galaxies: star clusters: general
Abstract:
The Panchromatic Hubble Andromeda Treasury (PHAT) survey is an ongoing
Hubble Space Telescope (HST) multi-cycle program to obtain high
spatial resolution imaging of one-third of the M31 disk at ultraviolet
through near-infrared wavelengths. In this paper, we present the first
installment of the PHAT stellar cluster catalog. When completed, the
PHAT cluster catalog will be among the largest and most comprehensive
surveys of resolved star clusters in any galaxy. The exquisite spatial
resolution achieved with HST has allowed us to identify hundreds of
new clusters that were previously inaccessible with existing
ground-based surveys. We identify 601 clusters in the Year 1 sample,
representing more than a factor of four increase over previous
catalogs within the current survey area (390 arcmin2). This work
presents results derived from the first ∼25% of the survey data; we
estimate that the final sample will include ∼2500 clusters. For the
Year 1 objects, we present a catalog with positions, radii, and
six-band integrated photometry. Along with a general characterization
of the cluster luminosities and colors, we discuss the cluster
luminosity function, the cluster size distributions, and highlight a
number of individually interesting clusters found in the Year 1
search.
Description:
This paper includes clusters identified in Year 1 PHAT (Panchromatic
Hubble Andromeda Treasury) imaging data, taken before 2011 June. A
full description of the PHAT observational design is available in
Dalcanton et al. (2012ApJS..200...18D 2012ApJS..200...18D), but we briefly summarize
relevant details below.
PHAT observations are grouped into 23 area units known as "bricks,"
each made up of 18 mosaiced HST fields of view in a rectangular 6x3
arrangement that covers a ∼12'x6.5' region of sky. Data are obtained
simultaneously at different field centers with the Advanced Camera for
Surveys (ACS; using the F475W and F814W filters) and Wide Field
Camera 3 (WFC3; using the F275W, F336W, F110W, and F160W filters)
instruments in two epochs, separated by ∼6 months. The Year 1 imaging
used in this work includes four full bricks (designated B01, B09, B15,
and B21) and the western halves of two additional bricks (B17W and
B23W). These data sample locations along the major axis of M31 from
the center out to a projected radius of ∼20kpc (see Figure 2).
See section 2 for further details.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 156 601 PHAT year 1 cluster catalog
table2.dat 156 237 PHAT year 1 possible cluster catalog
table6.dat 36 370 Background galaxy catalog
table8.dat 92 48 Revised Bologna catalog of M31 globular clusters
(Cat. J/A+A/416/917) revisions
table9.dat 37 21 *Hodge-Krienke catalog revisions
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Note on table9.dat : The Hodge-Krienke catalogs (HKC) are Krienke & Hodge
2007, Cat. J/PASP/119/7; 2008, Cat. J/PASP/120/1; Hodge et al.
2009, Cat. J/AJ/138/770 and 2010, Cat. J/PASP/122/745
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See also:
J/A+A/549/A60 : Ages and [Fe/H] of M31 globular clusters (Cezario+, 2013)
J/A+A/544/A155 : HST photometry of M31 globular clusters (Federici+, 2012)
J/AJ/143/14 : Lick indices of M31 globular clusters (Schiavon+, 2012)
J/MNRAS/402/803 : M31 globular cluster system (Peacock+, 2010)
J/PASP/122/745 : HST WFPC2 star clusters in M31. III. (Hodge+, 2010)
J/ApJ/725/200 : An updated catalog of M31 globular-like clusters (Fan+, 2010)
J/AJ/140/1043 : GCs in M31 and the Galaxy (van den Bergh+, 2010)
J/AJ/139/1438 : SED and age estimates of 104 M31 GCs (Wang+, 2010)
J/AJ/138/1667 : HST survey of young clusters in M31. III. (Barmby+, 2009)
J/AJ/138/770 : HST/WFPC survey of M31 bright young clusters (Hodge+, 2009)
J/A+A/508/1285 : Metallicity estimates of M31 GCs (Galleti+, 2009)
J/A+A/507/1375 : HST/ACS VI data of M31 globular clusters (Perina+, 2009)
J/ApJ/703/1872 : Compact star clusters in the M31 disk (Vansevicius+, 2009)
J/PASP/120/1 : HST WFPC2 star clusters in M31. II. (Krienke, 2008)
J/ApJS/177/174 : Star clusters in M31 (Narbutis+, 2008)
J/PASP/119/7 : HST WFPC2 star clusters in M31 (Krienke+, 2007)
J/A+A/471/127 : New globular clusters in M31 (Galleti+, 2007)
J/AJ/133/2764 : M31 globular clusters structural parameters (Barmby+, 2007)
J/A+A/456/985 : RVs of 76 M31 candidate clusters (Galleti+, 2006)
J/A+A/449/143 : Photometry of M31 globular cluster candidates (Ma+, 2006)
J/PASJ/56/1025 : Compact star clusters in SW field of M31 (Kodaira+, 2004)
J/A+A/416/917 : Revised Bologna Catalog of M31 GCs (Galleti+, 2004)
J/AJ/123/2490 : RV and [Fe/H] of M31 globular cluster system (Perrett+, 2002)
J/AJ/122/2458 : M31 globular clusters from HST (Barmby+, 2001)
J/AJ/119/727 : M31 globular clusters photometry (Barmby+, 2000)
J/AcA/48/455 : Globular Clusters in M31 and M33 (Mochejska+, 1998)
J/AJ/114/1488 : Globulars in M31 (Holland+ 1997)
J/A+AS/116/447 : M31 globulars clusters ellipticities (Staneva+, 1996)
http://www.bo.astro.it/M31/ : Revised Bologna Catalog of M31 globular clusters
http://www.astro.washington.edu/groups/phat : PHAT home page
Byte-by-byte Description of file: table[12].dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- PCID [1/1728] PHAT Cluster identification number
(<[JSD2012] PC NNNN> in Simbad)
7- 15 F9.6 deg RAdeg Right ascension in decimal degrees (J2000)
18- 26 F9.6 deg DEdeg Declination in decimal degrees (J2000)
29- 32 F4.2 arcsec Rap [0.45/6] Aperture radius
35- 38 F4.2 arcsec Reff [0.08/2.4]? Effective radius
41- 45 F5.2 mag F275W [15/30]? HST/WFC3 F275W band magnitude
48- 51 F4.2 mag e_F275W ? Error in F275W
54- 58 F5.2 mag F336W [15/28]? HST/WFC3 F336W band magnitude
61- 64 F4.2 mag e_F336W ? Error in F336W
67- 71 F5.2 mag F475W [15/25]? HST/ACS F475W band magnitude
74- 77 F4.2 mag e_F475W ? Error in F475W
80- 84 F5.2 mag F814W [13/27]? HST/ACS F814W band magnitude
87- 90 F4.2 mag e_F814W ? Error in F814W
93- 97 F5.2 mag F110W [12/28]? HST/WFC3 F110W band magnitude
100-103 F4.2 mag e_F110W ? Error in F110W
106-110 F5.2 mag F160W [11/31]? HST/WFC3 F160W band magnitude
113-116 F4.2 mag e_F160W ? Error in F160W
119-122 F4.2 --- Qual [1/2.5] By-Eye quality score (2)
125-129 F5.2 mag ApCor [-0.6/-0]? Aperture correction (1)
132-156 A25 --- AName Alternate names
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Note (1): Aperture corrections are provided such that
mTotal=mAperture+ApCor.
Note (2): a score between 1 and 3 (1=definite, 2=likely, 3=non-cluster) is
assigned independently by team members; the average is given here.
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Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Seq [1/370] Galaxy identification number
(<[JSD2012] NNN> in Simbad)
6- 7 I2 --- Brick [9/23] PHAT Brick Location (1)
10- 18 F9.6 deg RAdeg Right ascension in decimal degrees (J2000)
21- 29 F9.6 deg DEdeg Declination in decimal degrees (J2000)
32- 36 F5.2 arcsec Rad [0.2/15] Approximate galaxy radius
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Note (1): PHAT observations are grouped into 23 area units known as bricks,
each made up of 18 mosaiced HST fields of view in a rectangular 6x3
arrangement that covers a ∼12x6.5arcmin region of sky
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Byte-by-byte Description of file: table8.dat
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Bytes Format Units Label Explanations
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1- 7 A7 --- Name Revised Bologna catalog name
10- 13 I4 --- PCID [320/1673]? PHAT cluster identification number
17 I1 --- New [1/6]?=9 New RBC classification flag (1)
20 I1 --- Old [1/6] Old RBC classification flag (1)
24- 92 A69 --- Comm Comments
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Note (1): Flag codes follow the conventions of the RBC, with the addition of the
value "9" representing an entry that should be removed.
Global classification flag as follows:
1 = confirmed GC;
2 = GC candidates;
3 = Controversial object;
4 = confirmed galaxy;
5 = confirmed H II Region;
6 = confirmed star.
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Byte-by-byte Description of file: table9.dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- HKCID Hodge-Krienke cluster name
15- 18 I4 --- PCID [24/1435]? PHAT cluster identification number
22- 37 A16 --- New PHAT classification (Possible or Non-Cluster)
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 04-Feb-2014